Several methods exist for constructing a building, and more specifically, for erecting walls for a building. For example, walls may be constructed from precast and/or prestressed concrete exterior panels. In this method, walls may be formed, poured, and cured at an offsite facility (i.e., a location other than the worksite at which the walls will be installed), transported to the worksite, and installed by a crane or similar method. As another example, tilt-up walls may be erected to create the walls for a building. Tilt-up construction, also known as tilt-slab or tilt-wall construction, refers to the onsite formation of concrete walls. That is, horizontally extending forms are built at the worksite at which the walls will be installed, and concrete is poured into the forms and cured. Once cured, the forms are removed, and the tilt-up panels are erected by a crane or similar method. As will be appreciated, either method typically results in a wall panel having a relatively small thickness as compared to the width and height of the panel. Further, each wall panel is generally very heavy. For example, each wall panel may weigh up 140 tons, depending on the application. Thus, to maintain the wall panel in an upright position, bracing generally is required to, for example, resist lateral forces such as wind loads. The bracing typically comprises one or more legs or pole braces. Commonly, one end of a pole brace is affixed to a wall panel and the other end is anchored to a floor slab or other slab.
Typically, the pole braces can be positioned either inside the building or outside the building. As will be understood, anchoring to the inside of the building refers to anchoring where the pole braces are affixed to the interior side of the wall panels and anchored to, for example, a floor slab of the building. In many instances, such as, for example, when the resulting building is a storage facility, warehouse, or any other building where usable floor area is at a premium, inside anchoring is undesirable, as the space required for the pole braces translates to unusable floor area that is necessary for other construction-related tools and machines (e.g., a crane used to raise the walls into place). Additionally, for buildings taller than one wall panel, an additional “pour” or additional wall panel typically is required to be stacked atop the initial wall panel to meet the desired height of the building. This becomes problematic for wall panels anchored to the inside as there is not straightforward method to anchor the additional panels to the inside.
As shown in FIGS. 1A and 1B, and as will be understood, anchoring to the outside of the building refers to pole braces that are affixed to the exterior side of the wall panels and anchored to, for example, an extension of the floor slab of the building or some other slab or structure (or even the ground) exterior to the building. Alternatively, the wall panel can be anchored to a concrete block of sufficient height to maintain the wall in an upright position. Regardless of the bracing or anchoring method employed, outside anchoring can be undesirable. As will be appreciated, the parcel of land on which the building sits includes a finite land area, and bracing the wall panels on the outside of the building necessitates a smaller footprint of the building itself. That is, area of the land parcel that would otherwise be available to build on is instead set aside to provide space in which to install bracing. Alternatively, the bracing may encroach onto adjoining parcels. Thus, continuing the example in which the resulting building is a storage facility, warehouse, or any other building where usable floor area is at a premium, outside anchoring can also be undesirable, as the total usable space is once again diminished due to the space requirements of the bracing.
Additionally, erection of the wall panels is commonly accomplished by a crane that is positioned outside the footprint of the building being constructed. But due to space constraints, it may be difficult or impossible to position a crane outside the footprint of the building being constructed. For example, existing structures (e.g., existing buildings), the topography or vegetation (e.g., trees) of the land surrounding the parcel on which the building is being built, or other factors may surround the parcel. This further complicates the construction process and more specifically, erection of the wall panels.